Everest: how Jake Gyllenhaal got to grips with the world's highest mountain

Imported snow from Holland was among the secret weapons deployed by Everest director Baltasar Kormákur in his quest to make his 3D film about the disastrous 1996 expedition, when eight climbers died on the world’s highest mountain, as realistic as possible.

''It was the real stuff, minus 60 degrees; when we were shooting at Pinewood, we blasted it in their faces as hard as we could.”

“I wanted the actors to respond to the environment,” Kormákur said. “The more you draw from reality, the more likely you are to get reality.” Everest, which features Jason Clarke and Jake Gyllenhaal as Rob Hall and Scott Fischer, leaders of rival expeditions on the mountain, both of whom died in the tragedy, has been given the prestigious opening-night gala slot at the Venice film festival.

Watch the trailer for Everest

Speaking to the press before the official screening, Kormákur, an Icelandic-born film-maker, joked that he “had been practising for this movie every day as a kid, going to school in a blizzard”, and that popping outside during a “snow-blind blizzard” on his family’s farm in Iceland inspired his sense of what the film should be. “Except, add 29,000 feet to that.”

Kormákur explained that he and his crew had shot at progressively higher altitudes in Nepal and on the slopes of Everest itself, including the airport at Lukla, until altitude sickness prevented it. “We walked almost up to base camp, no vehicles are allowed there … at that point, we were shooting at the climber’s memorials, people started to get sick, and we had to evacuate pretty quickly. It’s one thing climbing up a mountain, which is really hard in itself, but it’s another to work a 12-hour day when you get there.”

The film crew also filmed in the Dolomite mountains, on the Italian-Austrian border, and added visual effects to blend in shots of the actual Himalayas. While stressing that no one was exposed to any unnecessary danger, he said the film benefited from sending a film unit headed by renowned mountain film-making specialist David Breashears to the summit two years before photography got under way. During a subsequent Everest ascent, the second unit was caught up in the 2014 avalanche (in which 16 Sherpas died). None of the film crew were harmed. “There’s a difference between pain and injury,” said Kormákur. “I put them through a lot of pain, but no injury.”

Controversy has persisted since the accident as to individual responsibility in contributing to the disaster, and sensitivities clearly remain as to how the protagonists have been portrayed. Gyllenhaal spoke about meeting Fischer’s children before the film and listening to their descriptions of him. “When you are re-creating something that actually happened, you have a tremendous responsibility. Scott’s children contacted me directly, and it was a beautiful thing to feel him through them.”

Kormákur said: “It’s a balance you have to strike. You want to tell a real story, you don’t want to pull any punches. Showing mistakes humanises them, instead of just sanitising them. That’s why we try to be real as possible.”